VESA video modes

Hello there! I need to start by saying that this project is awesome and I strongly believe it will spark the creation of some very creative pieces of software!

Nevertheless, I think it would have being awesome to add support for choosing one of the available VESA modes. Right now, you have to do it in real-time mode, while bootloader switches the processor to go to 64-bits and therefore, if you need to work with it, then you need to somehow go back to 16-bits in the kernel (or 32-bits with emulation?) and do the setup. Making bootloader do it might be the best idea (as well as give it an option to automatically choose the highest option).

As far as I understand, it can be quite a challenge, considering you have to fit it into 16-bit processor mode memory (512 first bytes?), but as far as I know, it is rather doable.

I think that this implementation from Redox OS can serve as a good example.

Cheers, Alex!

Start by tracing how the bootloader currently handles real-time video mode setup and the transition to 64-bit mode. Review the referenced Redox implementation in x86_64/vesa.asm for comparison. Done means the bootloader can choose an available VESA mode, including an option to select the highest available mode, before handing off to the kernel.